Can You Build a Garage With Thermalite Blocks?

Thermalite, as a technology, has been around for well over 7 decades, but only recently has it become a go-to choice in large construction projects, simply because there are too many advantages in using it to ignore it any longer. 

Thermalite can not only be used to build garages, it makes sense in a lot of ways to do so. It has a very high compressive strength and the insulative properties of Thermalite alone make it worthwhile.

There is nothing inherently dangerous about using Thermalite over concrete blocks. It doesn’t have any major disadvantages when used in the construction of a garage, however, it does have some that you should be aware of.

Advantages and Disadvantages of Thermalite

There are far more advantages to using Thermalite than there are disadvantages. Thermalite is incredibly lightweight while retaining the durability necessary to support incredible weights.

ProsCons
Low weight propertyIncredibly durableResists rot, mold, and mildewA high level of sound insulationA high level of thermal insulationResists high temperature and fireEnvironmentally friendlyResists extreme coldCracks or breaks with improper handlingAbsorbs the moisture from rendering too quicklyLack of availabilityExpensive

Thermalite makes an excellent for use as walls, not only because it has the support structure strength necessary to do the job, but because of its insulative properties. It strongly resists both heat and cold, serving as insulation all on its own.

If you build a garage with Thermalite in a moderate environment, it’s doubtful that you will have to insulate the walls at all. The only insulation that you would have to be concerned with would be in the roofing. 

Thermalite can also be easily molded into the size blocks you need as you go along. However, care has to be exercised in doing so, as Thermalite is known for being a bit on the brittle side, despite its strength properties. 

It can also be drilled rather easily, though epoxy glue is recommended to fill the drill gaps before applying the screws afterward. Thermalite is perfect for load-bearing walls and also for partitions and even fencing

The drawbacks of Thermalite are far fewer but are certainly not something that you should overlook. They happen to absorb moisture very quickly, which is not a good thing when you are using any kind of epoxy or liquid-based material to hold them together. 

They’re also not easy to find in the US. There are not a whole lot of manufacturers in the US that produce Thermalite on a regular basis, so there is often a lack of supply when demand is increased. 

With supply and demand issues not in balance, you will also find that they can be on the expensive side, although the costs range up and down throughout the year.

What is Thermalite Made Of?

Thermalite is an interesting blend of a number of components, including sand, pulverized fuel ash, cement, lime, processed waste, water, and aluminum powder. The pulverized ash component makes up about 80% of a single block of Thermalite, with the rest of the above materials making up the remaining 20%, to one degree or another. 

A Thermalite block that is exposed to a flame torch at 2400°F will be cool to the touch and relatively undamaged seconds after removing the heat source from the block. This makes Thermalite an interesting possibility for a hearth if you ever wanted something like that in your garage. 

Despite that extraordinary resiliency towards heat, Thermalite blocks are highly brittle and pieces will chip off with just a bump against something hard. However, their brittle nature also makes them very easy to shape to whatever size you need. They can be cut with precision, using nothing more than a handsaw. 

These blocks are also filled with air pockets, which gives them their unique, lightweight property. While some would indicate that they can be used in flooring, it’s generally not advised to do so because of how brittle they are. Despite its compressive strength, it still can’t outdo a concrete slab. 

Can You Screw Directly Into Thermalite?

One of the major concerns is that if you use Thermalite to build a garage, you won’t be able to hang anything on the wall because it is too brittle to accept screws or nails. There is some truth to that. Thermalite is certainly brittle and it will surprise you how easy it is to knock a chunk off of it.

If you want to start hanging stuff in your garages, such as tool racks, cabinetry, lighting, or even something like a flat screen TV, you will want to use Thermal Block Fixings, which are specifically designed for use in Thermalite. 

The problem with regular screws is not they will chip away the Thermalite, although there is a very tiny possibility that they might, its that they don’t hold very well in the porous material. Thermalite is infused with air pockets, which is part of what makes it brittle and part of what makes regular screws an anathema. 

You can drill a hole and fill it with epoxy before inserting your screw but you have to be exceptionally fast because Thermalite will suck the water right out of the epoxy in a hurry. Thermal Block Fixings can be placed by drilling a hole first, using a general purpose bit. 

Then, you screw the fixing in, which resembles a drywall anchor except it has threading. After you have finished inserting the fixing, you can insert a regular screw to hang up whatever you need to hang up.

It’s almost entirely like using drywall anchors, except you have to screw in the anchor rather than tapping it in with a hammer. 

All Things Considered

You can certainly use Thermalite when building your garage, so long as you know that there are a few limitations with the material and it doesn’t act like a standard concrete block or brick. 

If you decide to go with Thermalite, you will get a sturdy, long-term garage that is nearly self-insulated, highly resilient, and perfectly accommodating for any fixings that you want to go with, as long as you use specific fixings, rather than standard screws. 

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Can You Build a Garage With Thermalite Blocks?
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